1. Field of the Invention
The present invention relates to a silver halide color photographic photosensitive material and an image forming method using the silver halide color photographic photosensitive material and it relates to a image forming method improved in an image conservation property during storage, a silver halide photographic material provided with processing stability with ensured rapid high prodictivity and an image forming method by using the material, a silver halide color photographic photosensitive material with reduced replenishing amount of a processing solution and excellent in rapid processability in a compact laser scanning exposure type silver halide color photographic processing system, as well as an image forming method using the material. More specifically, it relates to an image forming method of stabilizing water washing in a rinsing step (water washing and/or stabilizing step) in a color development processing for a thin-layered silver halide color photographic photosensitive material excellent in the color reproducibility, a image forming method without lowering of a cyan concentration upon conducting continuous processing, as well as a silver halide color photographic photosensitive material at high saturation and with improved unevenness in solid images, and an image forming method using the same.
2. Description of the Related Art
In recent years, in the field of photographic processing services, photographic materials at high image quality which can be processed rapidly have been demanded as forming a part of services for users and as a means for the improvement of the productivity. In order to cope with the demand, rapid processing that is usually adopted these days enables to process a photographic material containing an emulsion at high silver chloride content (hereinafter also referred to as “high silver chloride printing material”) for a color developing time of 45 sec and to conduct total processing from the start of the developing step to the end of the drying step in about 4 min (for example, color processing CP-48S, manufactured by Fuji Photo Film Co., Ltd.). However, when compared with the rapid processability in preparing images of other color image preparation systems (for example, electrostatic transfer system, thermal transfer system, and ink jet system), even this rapid development processing system of the high silver chloride printing material can not be said to provide a satisfactory rapid processability and it has been demanded for a super rapid processing in which the total processing time from the start of the development to the end of the drying for the high silver chloride color printing material is less than 1 min.
For this purpose, various studies and attempts have been made for the improvement of the super rapid processing adaptability in the relevant field of art.
For example, as the means for the improvement of the super rapid processing adaptability, it has been studied (1) to reduce the coating amount of an organic coating material and the coating amount of a hydrophilic binder material by using a highly active coupler or a coupler having a large molecular extinction coefficient of a color dye, and (2) to use a silver halide emulsion of high developing speed. Further, it has also been known a method of making the development processing more rapid by coating a silver halide emulsion layer with lowest color developing speed (yellow coupler containing layer in existent color printing material) on the side remote from a support, which is disclosed, for example, in JP-A Nos. 7-239538 and 7-239539. Further, JP-A No. 2000-7673 defines, with an aim of rapid processing, the amount of binder and the amount of an oil soluble component coated to a silver halide photosensitive material and the concentration of the white area in a rapid processing.
Decrease of gelatin binder contributes to rapid processing since it accelerates intrusion of a color developing agent in the processing solution into a silver halide photosensitive material. However, it deteriorates the protective colloid function of oil droplets present in the silver halide photographic material or dye dispersed oil droplets after coloration, causing bleeding, etc. in color images and worsening the image conservation property. Further, while JP-A No. 2000-7673, etc. disclose addition of a water washing accelerator to a water washing stabilizing bath for decreasing the worsening of the white area due to the residue of a sensitizing dye or an irradiation preventive dye or addition of a brightening agent for suppression of yellow tinted color upon rapid processing, but salts present in the gelatin binder for the acceleration of washing lowers the protective colloid performance to also result in causing bleeding, etc. in color images, and worsening the color conservation property.
On the other hand, it is particularly poor in the color separation performance of a cyan color dye compared with after color image forming systems (for example, electrostatic transfer system, thermal transfer system and ink jet system) and JP-A Nos. 5-150418 and 11-212225 contain description regarding the improvement of color purity while enhancing the color image conservation property. However, an image forming method capable of satisfying the color image stability and, further, the color purity while considering the rapid processability and avoiding color image bleeding while possessing outstanding superiority over other color image methods has not yet been found.
Further, with a view point of stabilizing the performance by continuous processing, the high silver chloride printing material can not be said to have superiority compared with other systems and improvement for the robustness to the continuous processing stability has been demanded long since.
Therefore, various studies and attempts have been made in the relevant field such as for the improvement of the continuous processing stability.
For forming color photographic images, photographic couplers of three colors, i.e., yellow, magenta and cyan are incorporated into three types of photosensitive layers of different color sensitivities and, after imagewise exposure, processed by a color developer containing a color developing agent. In this step, a color dye is provided by coupling reaction with an oxidant form of a primary aromatic amine. Generally, the development processing step for the silver halide color photographic photosensitive material generally comprises a color developing step of forming color images, a desilvering step (bleach-fixing step) of removing developed silver and not developed silver, as well as a water washing and/or stabilizing step (rinsing step). In the desilvering step of removing the developed silver and silver halide, the developed silver is re-oxidized by a bleacher and fixed by a silver halide solubilizing agent, and the step is conducted by a single step using a single solution comprising a combination of a bleacher and a fixing agent. The solution is generally referred to as a bleach-fixing (or blix) solution.
As the silver bleaching agent in the bleach-fixing solution, organic acid complex ferric salts, among all, complex ferric salts of ethylene diamine-N,N,N′,N′-tetraacetic acid (hereinafter referred to as EDTA) is usually used. Further, with a view point of rapid processing and decrease for the liquid waste ingredients in the processing solution, complex ferric salts of 1,3-propane diamine-N,N,N′,N′-tetraacetic acid (hereinafter referred to as PDTA) are also used generally. On the other hand, in view of intense interest for the discharge of chelate agents with less biodegradability in the natural world and tending to solubilize toxic heavy metal ions along with increasing consciousness for the environmental protection, development for the substitutes thereof has been demanded and, for example, JP-A Nos. 4-313752, 5-265159 and 6-161065 describe chelating agents excellent in the biodegradability.
However, when the complex ferric salt described above is used as the bleaching agent for the color photographic agent, cyan color images with sufficient density can not sometimes be obtained. This phenomenon is generally recognized as reduction discoloration by leuco-transformation of a cyanine dye in a bleach-fixing solution (hereinafter referred to as blix discoloration). U.S. Pat. No. 4,591,548 points out the presence of complex ferrous salts in the bleach-fixing solution as a cause for the transformation of the cyan color dye into a leuco compound.
The effect of the bleach-fixing solution is attained effectively when it is in an oxidative atmosphere and aerial oxygen is supplied into the processing solution. Further, the blix discoloration can also be prevented by preventing lowering of the cyan density by oxidizing the complex ferric salts present in the solution. With the view point described above, the effect can be improved by enlarging a so-called an opening degree, that is, a portion where a processing liquid in a bleach-fixing bath processing tank is in contact with air. However, enlargement for the opening degree promotes evaporation of water during continuous processing to sometimes result in a problem such as deposition by thickening of the processing solution ingredient. Stabilization for the cyan density in a processing machine with reduced opening degree of the bleach-fixing bath is demanded. For this proposes, improvement by the silver halide color photographic photosensitive material is demanded.
On the other hand, in the color photographic development processing in recent years, simplification and rapid processing have been intended such as decrease in the replenishing amount and the shorting of the processing time. Lowering of the replenishing amount and increase in the processing operation efficiency in the desilvering step result in increase in the complex ferric salt tending to worsen the blix discoloration. Further, while lowering of pH in the bleach-fixing solution is effective for the shortening of the time in the desilvering step, lowering of pH in the bleach-fixing solution also results in a disadvantage of promoting blix discoloration of the cyan dye.
The following various approaches have been proposed to overcome the blix discoloration of the cyan dye. For example, U.S. Pat. No. 3,706,561, etc. disclose improvement by the change of the concentration and the composition of the bleach-fixing solution. U.S. Pat. No. 4,366,233 proposes to decrease the total coating amount of silver in the layer disposed below the cyan dye forming layer of a color photographic element. U.S. Pat. No. 3,820,997 describes improvement by various compounds in the processing bath. Further, U.S. Pat. No. 3,774,510 proposes addition of water soluble ionic compounds containing polyvalent elements in bleach-fixing bath. U.S. Pat. Nos. 4,151,680, 4,374,922 and 4,591,546 describe a group of preferred cyan couplers capable of overcoming the problems described above.
As a method of improving the blix discoloration, a method of improvement by using a certain type of hydroquinone or quinine derivatives is described, for example, in JP-A No. 63-316857. However, such prior art involves drawbacks that the effect is insufficient or the photographic performance such as image conservation property is sacrificed, and a great burden is put on the disposal of liquid wastes. Further, in the prior art described above, no sufficient solutions have yet been reached even in a case of using a bleach-fixing solution using EDTA complex ferric salts or PDTA complex ferric salts, as well as complex ferric salts of the biodegradable chelating agents. Accordingly, it has been demanded for the technique free from the foregoing drawbacks and having a greater effect for preventing blix discoloration of the cyan dye, also with a view point of rapid processing or undesired effects on the environment in recent years.
On the other hand, an attempt for the improvement of the blix discoloration of the cyan dye by using a polymer latex has also been conducted so far and, for example, JP-A Nos. 64-52136 and 2-289840 disclose methods of using polymer latexes having alkoxyalkyl groups on the side chains. However, the improving effect is still insufficient even with the compounds and, particularly, in a case of conducting rapid development processing with low replenishing amount rapidly and conveniently, it is necessary to improve the performance.
Polymer latexes formed by copolymerizing monomers having —COOH groups are well known in the field of photographic materials and, for example, U.S. Pat. No. 3,287,289 discloses a copolymer of n-butylacrylate and acrylic acid or methacrylic acid. Further, while JP-A No. 11-84559 describes that the improving effect is increased by controlling the pH of the coating solution to an acidic region, it can not be said that the improved level is at a sufficient level.
Further, in recent years, digital laboratories systems of recording images recorded on photographic films on photographic paper (photosensitive material) have been increased and processing stability can be ensured easily by calibrating correction. However, it is not preferred to conduct calibrating correction each time when coloring property changes, since such frequent corrections lower productivity.
The properties demanded for the photographic paper used for color printing so far have been performances such as image quality, rapid processibility and image conservation property, but in recent years the possibility of printing based on digitalized image information has arisen as one of important properties. This is because systems of preparing color printing by digitalized image data as represented by Frontier series manufactured by Fuji Photo Film Co., Ltd. and infrastructure capable of easily obtaining high image photographic prints by utilizing digital image processing techniques have been established. Since optimization of printed images based on more complicate algorithms will be possible in the future by the improvement of the computer processing performance more and more, it is expected that the image quality of color prints will be improved further. Further, there are subjects for developing digital print systems and improving the digital adaptability of photographic paper such as capability of providing various services depending on users by improvement in the compatibility with input equipments for digital cameras, digital video movies or scanners other than negative films.
On the other hand, commercial production systems for color prints are generally classified into mass-productive, low cost and intensively served, so-called major laboratories, and small-lot productive on-site, community based mini-laboratories. In view of the difference in respective color print production systems, means for solutions can not generally be in common even for common subjects, but selective production of photographic paper specialized to respective systems is not preferred since this will result in loss in the production sites and loss in the distribution process of photographic materials.
Accordingly, various improvements are necessary such that the photographic paper can cope with both systems of analog (surface) exposure in major laboratories and scanning exposure by a solid or semiconductor laser light in the Frontier systems.
In a case of forming images based on digitalized image data such as in CG (computer graphics), an importance resides in capability of reproducing so-called solid image which is uniform, and has an extremely small density difference with relatively large area. However, it has been found that rough unevenness, which is different from banding, tends to occur when scanning exposure is conducted by using a solid or semiconductor laser light in the development processing system of mini-laboratories with less replenishing amount compared with the development processing in large scaled laboratories by using a coupler forming a cyan dye of high saturation.